This invention relates to a tensioning device. A tensioning device is used to tighten a chain, cable, strap or similar material. There are several types of tensioning devices, including but not limited to; load binders and turnbuckles.
Load binders are tools used to secure cargo or loads to trucks, ships, vessels or other types of load carriers. Cargo or load is a generic term and is used in the broadest sense possible, including but not limited to crates, boxes, logs, pipes, rods, and containers. Typically load binders secure loads to the carrier during transport or movement. A load binder is an apparatus for tensioning a chain, cable, strap or similar material to secure a load.
Turnbuckles are devices for creating tension using threaded components to lengthen or shorten chains, cables, straps or similar material creating a tension in the material. There are many uses and varieties of turnbuckles in the market. A tension device is often time used for strapping down cargo or loads. A cable, chain or strap is strategically placed over or around a load and then secured to a carrier. The turnbuckle is used to tighten the cargo or load to reduce movement. It is apparent from the various descriptions of turnbuckles and load binders that they perform a similar function; tensioning a chains, cable, strap or similar material.
In the description presented in this application, the inventor is using the term “chain” for the material that is tensioned. Chain is a generic term and encompasses cable, straps, ropes or other similar type material. The tensioning device in the present invention can be used with the various types of material known to those skilled in the art of load binders and turnbuckles. The present description makes no claims on the various materials, such as chains, used in tensioning devices, load binders or turnbuckles. It has been noted by the inventor that the various types of tensioning device on the market and in the prior art have several drawbacks from the present invention.
There is a plethora of tensioning devices in the prior art. The chain, cable, strap or similar material for securing a load has a means for tightening the chain, cable, strap or similar material to secure the load to the carrier. See U.S. Pat. No. 139,969 to J. Paff, describing a lever type action used to tighten a chain as the lever is leveraged in the apparatus against the chain and then secured. And, U.S. Pat. No. 4,058,291 to K. Shreyer, et al., describing an apparatus for tensioning a chain with a lever and means for securing the lever during a retrogressive movement as the chain is tightened. It has been observed by the inventor that these types of tensioning devices have levers that are prone to springing free and can cause harm to a user or unloosen loads. Additionally, the lever can get in the way and does not store efficiently during transport.
Load binders, commonly used by transporters, include typical lever action devices. Once the chain is tightened to an appropriate tension, the lever is secured or latched such that the lever is under some tension with a locking mechanism to secure the lever. There are many types of lever and locking mechanisms but in the present state of load binders, the lever when the load is secured has tensioned force that once released from the locking mechanism springs open with force and has been observed by the inventor to be potentially harmful to operators or cargo.
The present invention replaces this type of leveraged tension with tensioning device that utilizes the threaded mechanism commonly found in turnbuckles. This eliminates the possibility of the tensioned lever springing open and possibly harming an operator or prematurely releasing the load.
Some load binders, similar to the present invention, use screw or threaded mechanisms for tightening the chain. See, U.S. Pat. No. 4,567,627 to W. Patterson, III, which discloses a load binder with a telescopically retrievable inner and outer sleeve in which the chain is tightened as a threaded connection is tightened and the chain is attached to the sleeves. The present invention improves upon this type of invention by making the apparatus more compact and more efficient as the rotation of the present device more rapidly and more efficiently tightens said chain through a more direct translation of angular movement into axial movement. The present invention uses fewer parts and a more direct translation for tightening the chain. In addition, the present invention can use various means or tools for tightening the chains instead of an attached lever or handle such as an impact wrench.
A similar but less efficient and more complex device compared to the present invention is described in U.S. Pat. No. 4,973,185 to H. Thaller. This chain tightening device uses a gear and two rods to rotate and transmit the applied angular movement producing tension in the cable when the threaded rods displace a coupling device. The turnbuckle of this invention relies on the tensioned force to be transmitted through the body of the turnbuckle and uses two rotating rods for translating the angular force into axial force. The present invention uses one rod with fewer parts and a more efficient transmission of converting angular rotation into axial displacement thereby tensioning the chain more efficiently. There are fewer parts in the present invention from the prior art and the reduction in gearing allows for a lighter weight.